We are applying to continue our role as one of the five current Clinical Coordinating Centers (CCCs) in the Randomized Intervention for Children with Vesicoureteral Reflux (RIVUR) study (RFA-DK-09-502). The RIVUR trial has not yet reached its full recruitment and it is anticipated that this proposed 3-year extension will allow for full recruitment and follow-up of the 600 children proposed in the original protocol. Recruitment is expected to be completed by May 2011 so that all follow-up procedures can be completed by May 2013. By end of the current funding period (May 2010), we expect to have enrolled the agreed upon 120 children for the Children's Hospital of Pittsburgh (CHP) CCC. The additional 3-year extension will allow us to (1) continue to follow children already enrolled for the full 2-year follow-up period, and (2) to recruit and follow up to an additional 30 children. Given our mean rate of enrollment to date (3.5 children per month), we expect to enroll these 30 children during the first 9-12 months of the extension period, giving us sufficient time to complete 2-year follow-up for these patients. The CHP CCC has clearly demonstrated its ability to recruit, retain and complete follow-up of children in the RIVUR study. We have enrolled 100/373 children enrolled to date in RIVUR, we are the single site with the most children enrolled in the study; the closest single site has 49 children enrolled. Our retention of children is evidenced by rates above 95% overall in completion of data collection forms throughout the study.